GENOTYPIC STRUCTURE OF A DROSOPHILA POPUL ATION FOR ADULT LOCOMOTOR-ACTIVITY

Analysis of the variation of adult locomotor activity in four samples taken at different times from a natural population of Drosophila melan ogaster showed that the total variation of this trait is relatively st able in time and has a substantial genetic component. Genotypic struct ure of the population for locomotor activity is characterized by the p resence of large groups of genotypes with high and low values of this trait. A possible explanation for the presence of such groups in a pop ulation is cyclic density-dependent selection.